If I could magically place a copy of Mark Lilla's The Once and Future Liberal: After Identity Politicsinto the hands of every Democratic Party politician, activist, major donor, pollster, and consultant in the country, I would. This slim (141-page) polemic is the rare book that could really make a difference in how people think and act, speak and vote. (And yes, I would say that even if its author were not my friend and former teacher.)

Lilla has written the most admirable and necessary political broadside in years — all the more so because it steers completely clear of the internecine debates that have roiled the Democratic Party since the 2016 primaries. Readers will find no re-enactment of the interminable Hillary Clinton-Bernie Sanders rivalry, no arguments about how the party simply must track toward the left or the center to regain an electoral advantage.

On such questions Lilla remains agnostic. What he wants is for Democrats to win elections, from the presidency on down through Congress to state legislatures, town councils, school boards, and local judgeships. And to do that, he claims, the single most important thing is for them to break their addiction to identity politics.

Lilla first made a version of this argument in a New YorkTimes op-ed that sparked a thousand arguments shortly after the November 2016 election. The version elaborated here is even more cogent. The Once and Future Liberal is above all a book about political rhetoric and what the rhetorical focus of Democrats on sub-political identities (race, ethnicity, gender, sexual orientation, etc.) reveals about the vision of politics 21st-century liberals embrace, espouse, and practice.

What such rhetoric reveals is that over the past few decades liberals have effectively abandoned politics, which involves thinking "about the common good and what must be done practically to secure it," in favor of "a pseudo-politics of self-regard and increasingly narrow and exclusionary self-definition." Instead of cultivating a sense of "we — of what we are as citizens and what we owe to each other," liberals have become "mesmerized by symbols," more interested in recognizing and affirming the sense of grievance cultivated by the members of discrete sub-political groups than in offering "a vision of our common destiny based on the one thing that all Americans, of every background, actually share. And that is citizenship."

As such formulations reveal, Lilla isn't so much rejecting a politics of identity as skewering the tendency of "identity liberals" to focus exclusively on sub-political identities. Politics rightly understood is about defining who we are as a political community — what it means to be an American, what we owe to one another as citizens, as members of a collective body, as parts of a whole, engaged in a common enterprise.

The problem with practicing identity politics at the sub-political level is that it becomes just another form of individualism, replicating in a "less sentimental and more sanctimonious" idiom the anti-political outlook that came to power in the United States with Ronald Reagan. Whereas Reagan described a country of atomized individuals liberated from government (including from calls for public sacrifice of any kind), Democrats came to define politics as a form of self-exploration. Look into yourself, explore your background, situate yourself in relation to the various identity categories to which you belong, fasten on to the injustices these groups have suffered at the hands of powerful Others, and then demand recompense. This way of conceiving of politics has rendered incomprehensible JFK's ringing call to civic service (What can I do for my country?) and replaced it with a "deeply personal one: What does my country owe me by virtue of my identity?"

Lilla claims that this shift away from civic consciousness has trapped identity liberals in a "strategic contradiction" that inadvertently contributes to validating the right's hostility to government spending on public goods.

When [identity liberals] call for political action to assist their group X, they demand it from people they have defined as not-X and whose experiences cannot, they say, be compared with their own. But if this is the case, why would these others respond? Why should non-Xers give a damn about Xers, unless they believed they shared something with them? Why should we expect them to feel anything at all? [The Once and Future Liberal]

In place of making broader-based civic appeals, identity liberals substitute a rhetoric of hectoring evangelism that nearly always backfires. "That one now hears the word woke everywhere is a giveaway that spiritual conversion, not agreement, is the demand." Yet elections "are not prayer meetings" or "therapy sessions or occasions to obtain recognition. They are not seminars or 'teaching moments.' They are not about exposing degenerates and running them out of town."

They are, instead, about persuasion. Which is why winning the country back from the right and bringing about real and lasting change will require Democrats to "descend from the pulpit." The only solution to liberalism's political defenestration, Lilla insists, is more and better politics — more and better appeals to the citizenship all of us share. It is citizenship that can provide "a political language for speaking about a solidarity that transcends identity attachments," a solidarity that justifies not only individual rights and the self-assertion of sub-political identities but also policies rooted in our duties and obligations to one another.

It's a rousing message — but also one bound to make identity liberals quite angry. If they seriously engage with the argument, including Lilla's provocative reading of American political history since the New Deal and his closing case for a renewal of civic education to go along with a revitalized civic liberalism, they will be forced to rethink a lot of assumptions. And if they do that, not only will the Democratic Party be better placed to retake territory lost to the right in recent years. They will also have laid the foundations for a new, more confident and ambitious, era of American liberalism.